The Forest Republican. [volume] (Tionesta, Pa.) 1869-1952, 1887-02-02
SCIENTIFIC AND INDUSTRIAL.

Professor Hughes says silk ribbon is
a better lightning conductor than a rod
of metal.
Astronomical photography has sue
ceeded in reproducing stars down to the
thirteenth magnitude.
A Russian engineer says that he has
discovered a process Of reducing petro-
leum to the form of crystals, which may
be easily and safely transported to any
distance and then reconverted into liquid
form.
One of the most ingenious mechanical
devices recently introduced is saw with
out teeth, which will cut a steel rail in
two minutes The saw in question is
run by au eight-horse power engine
more power than is required to run all
the other machinery in the shops Sis
thirty eight inches in diameter, and
ree-eighths of an inch thick at the
edge.
A curious application has recently been
made of electricity to condense dusts and
fumes. II air filed with smoke is charged
with electricity, the smoke at once flies
to the sides of the containing vessel in
way that appears almost magical. In the
same way electricity will cause fine dusts,
which are in suspension, and which are
often very difficult to remove from the
air, to condense, or coagulate so as to be
easily removable.
1t was observed by HALEY that the
time of the moons revolutions round the
earth has for several thousand years been
decreasing or her velocity has been in
creasing. This phenomenon remained
for a considerable time inexplicable at
last Laplace, in 1881, discovered the
cause in the varying eccentricity of the
earth's orbit, which has been on the de-
crease since about $4,000 b. c. Since
that time the moon has been gradually
coming nearer to the earth, and this will
go on till 36, 900 years after Christ, when
the eccentricity of the earth's orbit will
begin again to increase.
When a spider is preparing to moult
it stops eating for several days and fast
ems itself by short line of web to one of
the nam lines of its snare, which holds
it firmly while it proceeds to undress.
! The skin cracks all around the thorax,
and is held only by the front edges. Next
| the abdomen is uncovered. Now comes
/ the struggle to free the legs; 1t works
| and kicks vigorously, and seems to have
/ very hard work. But continued perse-
verance of about fifteen minutes brings il
out of the old dress, and it seems almost
/ lifeless, and is limp and helpless for sew
eral minutes, but gradually comes back
to life and looks brighter and prettier
/ than before.
Lightning flashes have ometimes been
observed which, starting from one point,
have ended in several. Some remarka-
able forms of flash have been Lately de.
scribed by Herr Leyst of Pawowsk OBJ
servatory. In one case flash went a GER
tain distance in northeasterly direction,
then divided, the two branches forming
an angle of about 7jo. When these had
reached about 35' from each other, they
turned and united again to one line. The
path of the lightning thus formed q
quadrilateral figure. 1t was further OBJ.
served that the lightning flashed back
in the same path, as if there were an os
cillating discharge. In another inter
esting flash, the path was not crooked
line, but wavy band, which was lit up
four times in succession with equal bril-
liancy. The time between the second
and third and the third and fourth flashes
seemed longer than that between the first
and second. The thunder which fol.
lowed lasted about eighty seconds